Abstract
Dry ice (DI, solid carbon dioxide) and liquid carbon dioxide (LC) are both used in airborne glaciogenic cloud seeding, but no studies have objectively compared the efficacies of those two seeding agents. This paper describes a numerical model that involves the microphysical processes associated with airborne cloud seeding, and describes numerical simulations done to compare the efficacies of airborne DI and LC seeding in enhancing precipitation. Simulation results suggest that seeding effects appear faster for DI, and that the total amount of surface precipitation is almost the same for DI and LC seeding. Our results are counter to previously published assertions that LC is generally superior to DI in enhancing precipitation through airborne seeding in any type of clouds.
